Viscous pump for unitized bearing lubrication system

ABSTRACT

An individual lubrication system for a bearing with a viscous pump, gravity feed tank and heat exchanger integrated within the bearing housing. The viscous pump scraper serves to support the viscous pump casing from a universal connection so that hydrodynamic alignment between the casing and the pump disk is maintained for high-speed pumping.

United States Patent Wagner 1 1 Jan. 18, 1972 [54] VISCOUS PUMP FORUNITIZED 3,198,113 8/1965 Feller ..415/90 ux BEARING LUBRICATION SYSTEM2,351,431 6/1944 Irons ..415/90 1,496,849 6/1924 Howarth .....308/127Inventor: James E Wiener, Lynn, Mass. 1,919,138 7/1933 Wake ..308/127[73] Assigneez General Electric Compmy 2,730,297 1/1956 Van Dorsten eta1 ..415/90 [22] Filed: Apr. 16, 1970 Primary ExaminerC. J. Husar IAtt0rneyWilliam C. Crutcher, Bryan C. Ogden, Frank L. [211 App. 29l25Neuhauser, Oscar B. Waddell and Joseph B. Forman [52] US. Cl ..415/90,101/157, 308/127 [57] ABSTRACT [51] Int. Cl ..F01d l/36 An individualubrication s ystem for a Ibeanng with a vlscous [58] Field of Search..415/90, 308/127, 101/ P p g y feed tank and heat exchanger integratedwithin the bearing housing. The viscous pump scraper serves to sup portthe viscous pump casing from a universal connection so [56] ReierencesCited that hydrodynamic alignment between the casing and the UNITEDSTATES PATENTS pump disk is maintained for high-speed pumping.

3,396,664 8/1968 Smith ..415/90 4 Claims, 6 Drawing Figures PATENTED m18 11-172 sum 1 OF 2 Qooooooooooo ofiooooocoooo QOOOOOOO oooooooooINVIENTOR: JAMES B. WAGNER,

HIS ATTORNEY.

PATENTEUJANWW 3,835,578

SHEET 8 UF 2 30 D 5 28 [-Z f X m g m 1y 22b if J8 F|G.5 22b 35 I9 l-IQINVENTOR JAMES B. WAGNER,

BY w 44,224.

32 HIS ATTORNEY.

VISCOUS PUMP FOR UNITIZED BEARING LUBRICATION SYSTEM BACKGROUND OF THEINVENTION This invention relates generally to an integrated viscous pumpand gravity feed bearing lubrication system, and more particularly toimprovements in the viscous pump casing and scraper construction.

Conventional lubrication systems for large rotating equipment such asturbine-generators have employed a central pump with pipes leading tothe various hearings to provide a flow of lubricating oil to thebearings. There has been a need for a simple means to lubricate eachbearing separately without the need for extensive piping to and from acentral pump and heat exchanger.

It has been suggested in the prior art in US. Pat. No. 3,396,664 issuedto R. J. Smith on Aug. 13, 1968 that a viscous pumping disk can be usedto transfer lubricating oil from a sump in the bottom of a bearinghousing to a gravity feed tank which provides a flow of oil to thebearing journal. In the Smith patent, a spring-loaded scraper was usedto maintain small clearances between the scrapers and a rotating viscousring. An intermediate ring rotating at half speed was used between theviscous pumping disk and the pump casing to provide laminar flow betweenthe disk and the ring and between the ring and the casing. Improvedconstructions have been sought which would insure pumping capabilitywithout turbulence or flow separation of the lubricating oil from thedisk at high disk speeds.

Since the principle of a viscous pump is dependent upon the ability ofthe disk to pick up lubricating oil in the bottom of the casing byviscous drag and to carry it to the scraper at the uppermost part of thedisk, the clearances between disk and its casing are of vital concern inmaintaining the proper hydrodynamic relationships. Proper scraperpressure must be maintained so that undue scraper wear is notexperienced and the oil is removed properly from the disk.

Accordingly, one object of the present invention is to provide animproved scraper and casing support structure for a viscous drag pump.

Another object of the invention is to provide an improved unitizedbearing lubrication construction wherein a viscous pump is incorporatedin the bearing housing to operate at shaft speed with a minimum ofturbulence or flow separation of the lubricating fluid.

DRAWING The subject matter which is regarded as the invention isparticularly pointed out and distinctly claimed in the concludingportion of the specification. The invention, however, both as toorganization and method of practice, together with further objects andadvantages thereof,.may best be understood by reference to the followingdescription, taken in connection with the accompanying drawing, inwhich:

FIG. 1 is a horizontal elevation drawing, partly in section, showing thecomplete unitized bearing lubrication system,

FIG. 2 is an end view of the viscous pump assembly, taken along lines11-11 of FIG. 1, and

FIGS. 3, 4, and 6 are cross sections taken at various points through theviscous pump assembly of FIG. 2 as indicated by arrows IIIIII, IV-lV,VV, and VI-Vl respectively.

SUMMARY OF THE INVENTION Briefly stated, the invention is practiced bydisposing a viscous pump assembly with the bearing assembly in a commonhousing with a gravity feed tank in the upper part of the housing and aheat exchanger in the lower part of the housing. The viscous pump casingand feed tube are supported via a universal support directly upon ascraper which in turn rests upon the viscous pumping disk. The casingtherefore can follow movements of the shaft. The universal supportprovides for small aligning motions of the casing relative to the diskwithout varying scraper pressure or orientation of the scraper.

These movements are effected by the hydrodynamic pressures generated bythe pumped fluid.

DESCRIPTION OF THE'PREF ERRED EMBODIMENT Referring now to FIG. 1 of thedrawing, a common housing, shown generally as 1, includes a viscous pumpassembly 2, a bearing assembly 3, a gravity feed lubricating oil tank 4in the top of housing 1, and a heat exchanger 5 in the bottom ofhousing 1. A rotatable shaft 6 extends through the housing and labyrinthseals 7, 8 prevent the escape of liquid or vapor.

The construction of the bearing assembly 3 is conventional. A hearingjournal sleeve 9 with attached oil deflectors 10, has a lining 11 withinternal grooves (not shown) connected to an oil supply pipe (notshown). The sleeve 9 is supported within a split casing 12 which in turnis held within a pillow block sup port 13 in conventional fashion.

The gravity feed tank 4, which has a level maintaining weir (not shown)maintaining an oil level 14, has an oil outlet pipe 15 connected withthe aforementioned pipe supplying oil to the bearings in a conventionalmanner. Tank 4 also has an overflow chamber 16 from which excess oil iscirculated through an overflow pipe 17 to the bottom of housing 1.

A heat exchanger 5 is submerged in the lubricating oil in the bottom ofthe chamber to provide constant cooling of the oil. The oil level isindicated at 18.

Referring to the viscous pump assembly, a rotating disk 19 is attachedto the shaft by means of an integral hub shrunk onto shaft 6 at 21,although disk 19 could be-made integral with the shaft. The pump casing22 is supported on the scraper 23 by a universal support comprising aball and pin, or equivalent universal arrangement, indicated at 24. Apump discharge tube 25 carries fluid removed. by scraper 23 to thegravity feed tank 4.

The details of the viscous pump, casing and scraper assembly are moreclearly seen by reference to the partial sectional end view of FIG. 2.As indicated there, the scraper 23 rests on the periphery of disk 19 ona bearing pad 26. A cap 27 rests on the scraper 23 by way of theuniversal support 24 which will be more particularly discussed later inconnection with FIG. 6.

The casing 22 is made up of upper and lower halves 22a, 22b, which areattached together at a horizontal joint by threaded connectors 28. Thecap 27 is connected to the upper casing half 22a and also supports thedischarge tube 25.

Other features of the casing include relief slots 30, 31 on the inactiveside of the casing beyond the scraper. A stationary dam 32, which couldalternatively serve as a bottom scraper, serves to separate the pumpinlet 33 and an excess fluid outlet 34. Various other features of thecasing configuration may be seen by reference to FIGS. 3-6 which arecross sections as indicated in FIG. 2.

FIG. 3 illustrates the casing and disk interface on the active orpumping side, i.e., between inlet 33 at the bottom and scraper 23 at thetop. The casing includes a feed slot 35 defining a clearance between thecasing and the disk through which the major quantity of lubricating oilis transported from the bottom to the top of the pump casing.

FIG. 4 shows a relief slot section on the inactive or nonpumping side,i.e., between the scraper 23 and the excess fluid outlet 34. The casingwall relief slots 30, 31 relieve hydrodynamic pressures between the diskand easing due to any excess fluid which is transported downward towardthe outlet 34. This excess fluid is deflected by dam 32, or bottomscraper, so that there will be no interference with fluid pickup atinlet 33.

Referring now to FIG. 6, which particularly illustrates the novelsupport assembly, scraper 23 has a cylindrical recess 23a in which isdisposed a ball 36. A pin 37 is screwed into the cap 27 and rests on theball. Slight clearances are provided around the pin and around thescraper so that small universal movements may take place, which aregreatly magnified in terms of possible casing alignments with respect tothe disk 19 as should be apparent from a consideration of FIG. 2 of thedrawing. Selfnaligning spherical seats could also be used in place ofthe ball.

OPERATION The operation of the invention will be apparent from thefollowing description. Oil is picked up by viscous drag in adhering tothe disk 19 as it passes through the cooled oil in the bottom of thebearing housing 1. The oil is transported from the bottom to the top ofthe assembly in the passage afforded by feed slot 35 shown in FIG. 3until it contacts the scraper 23. Thereupon it is sheared off of thedisk and the dynamic pressure head causes the oil to flow upward throughthe discharge pipe 25 into the gravity feed tank 4. Thereafter, itpasses downward through pipe to the bearing. Bearing discharge oil, aswell as recirculated excess oil discharged through pipe 17, is cooledby-the heat exchanger 5 and recirculated to the viscous pump inlet.

It is particularly to be noted that the entire support of the viscouspump casing 22 and feed pipe 25 is via the universal connection 24 andscraper 23. The scraper pressure is due to the weight of these parts onthe scraper and hence constant pressure is afforded.

The universal connection 24 permits small movements of the casing withrespect to the disk so that the scraper can always contact the disk atthe correct angle and with constant pressure.

The foregoing described construction of the pump casing and feed pipesupport assembly on the scraper by means of a universal connectorprovides an exceedingly simple and compact means for incorporating aviscous pump lubrication feed in a bearing housing. The universalconnector prevents misalignment or binding and by the fact that constantpressure is always present on the scraper, it has been possible toincrease the pumping capacity of a viscous pump at high speeds withoutsignificant turbulence or flow separation which has accompanied priorart pumps of this type.

While there has been described herein what is considered to be thepreferred embodiment of the invention, other modifications will occur tothose skilled in the art, and it is intended to cover in the appendedclaims all such modifications as fall within the true spirit and scopeof the invention.

What is claimed as new and desired to secure by Letters Patent of theUnited States is:

l. A viscous pump assembly comprising:

a reservoir of viscous fluid,

a rotating disk communicating at its lower edge with said a scrapermember disposed on the top of said disk and having a surface resting onthe disk peripheral surface,

a casing loosely surrounding the disk periphery and defining an inlet tothe disk within said viscous fluid, and

universal support means adapted to carry the weight of said casing fromsaid scraper and permitting universal relative movements between casingand scraper.

2. The combination according to claim 1, wherein said universal supportmeans comprises a pin attached to the casing and extending downwardly torest upon a ball carried within said scraper member.

3. The combination according to claim 1, wherein said casing defines afeed slot opposite the disk periphery between said casing inlet and thescraper on the active side where the disk is traveling upward, andwherein said casing wall defines relief slots through the casing wallopposite the disk periphery on the inactive side of the casing where thedisk is traveling downward, whereby pressure relief of excess fluid isprovided.

4. A viscous pump assembly comprising:

a reservoir of viscous fluid,

a rotating disk communicating at its lower edge with said a scrapermember disposed on the top of said disk and having a bearing surfaceresting on the disk peripheral surface, said scraper also de imng arecess with a ball disposed therein,

a nonrotating casing loosely disposed about the disk, said casing havinga first arcuate wall portion defining a feed groove opposite the diskperiphery for containing viscous fluid transported upwardly to thescraper, and further having a second arcuate wall portion definingrelief slots therethrough for relieving pressure of excess fluid as thedisk travels downwardly,

a cap member connected between the first and second wall portions todefine a chamber containing said scraper member, said cap member havinga pin extending downwardly into said scraper recess and adapted tosupport the casing from said scraper while permitting small universalaligning movements.

1. A viscous pump assembly comprising: a reservoir of viscous fluid, a rotating disk communicating at its lower edge with said fluid, a scraper member disposed on the top of said disk and having a surface resting on the disk peripheral surface, a casing loosely surrounding the disk periphery and defining an inlet to the disk within said viscous fluid, and universal support means adapted to carry the weight of said casing from said scraper and permitting universal relative movements between casing and scraper.
 2. The combination according to claim 1, wherein said universal support means comprises a pin attached to the casing and extending downwardly to rest upon a ball carried within said scraper mEmber.
 3. The combination according to claim 1, wherein said casing defines a feed slot opposite the disk periphery between said casing inlet and the scraper on the active side where the disk is traveling upward, and wherein said casing wall defines relief slots through the casing wall opposite the disk periphery on the inactive side of the casing where the disk is traveling downward, whereby pressure relief of excess fluid is provided.
 4. A viscous pump assembly comprising: a reservoir of viscous fluid, a rotating disk communicating at its lower edge with said fluid, a scraper member disposed on the top of said disk and having a bearing surface resting on the disk peripheral surface, said scraper also defining a recess with a ball disposed therein, a nonrotating casing loosely disposed about the disk, said casing having a first arcuate wall portion defining a feed groove opposite the disk periphery for containing viscous fluid transported upwardly to the scraper, and further having a second arcuate wall portion defining relief slots therethrough for relieving pressure of excess fluid as the disk travels downwardly, a cap member connected between the first and second wall portions to define a chamber containing said scraper member, said cap member having a pin extending downwardly into said scraper recess and adapted to support the casing from said scraper while permitting small universal aligning movements. 